Larry D. Barnes, Ph.D.
Professor and Deputy Chairman
Department of Biochemistry
|
Location: |
MED, Office - 542C-1; Labs - 518B, 519B, 520B |
|
Phone: |
Office - (210) 567-3730; Lab - (210) 567-3701 |
|
Fax: |
(210) 567-6595 |
|
E-mail: |
|
|
Web Links |
http://biochem.uthscsa.edu/~barnes |
Research Interests:
Current research focuses on the determination of the role of diadenosine oligophosphates, ApnA, n=3-6, in cellular functions of the yeast, Saccharomyces cerevisiae, and yeast, Schizosaccharomyces pombe. ApnA have been proposed to be regulatory nucleotides in growth and signals of oxidative stress in lower eukaryotes and prokaryotes. In higher eukaryotes ApnA are vasoactive agents, serve autocrine functions in platelets and chromaffin cells, and affect target cells via purinergic-type receptors. The functions of ApnA are being investigated in yeast by increased expression and disruption of the genes encoding ApnA degradative enzymes. Manipulation of gene expression and subsequent perturbation of in vivo concentrations of ApnA should permit the identification of phenotypes related to functions of the ApnA. Additional studies focus on structure and function of the human Fhit protein, a tumor suppressor. Fhit is an Ap3A hydrolase that has 52% sequence similarity to the S. pombe Ap4A hydrolase.
Unique Technical and Clinical Research Capabilities/Instrumentation:
Measurement of dinucleotides and nucleotides by HPLC
Publications:
Huebner, K., Garrison, P. N., Barnes, L. D., and Croce, C. M. The role of the FHIT/FRA3B locus in cancer. Ann. Rev. Genetics 32, 7-31 (1998)
Ingram, S.W., Stratemann, S.A., and Barnes, L.D., Schizosaccharomyces pombe Aps1, a diadenosine 5', 5'''-P1, P6-hexaphosphate hydrolase that is a member of the nudix (mutT) family of hydrolases: cloning of the gene and characterization of the purified enzyme. Biochemistry 38, 3649-3655 (1999).
Abend, A., Garrison, P.N., Barnes, L.D., and Frey, P.A. Stereochemical retention of configuration in the action of Fhit on phosphorus-chiral substrates. Biochemistry 38, 3668-3676 (1999).
Safrany, S. T., Ingram, S. W., Cartwright, J. L., Falck, J. R., McLennan, A. G., Barnes, L. D., and Shears, S. B. The diadenosine hexaphosphate hydrolases from Schizosaccharomyces pombe and Saccharomyces cerevisiae are homologues of the human diphosphoinositol polyphosphate phosphohydrolase: the significance of the overlapping substrate specificities in a mutT motif. J. Biol. Chem. 274, 21735-21740 (1999)
Key Words:
dinucleoside oligophosphates; yeast; enzymology; nucleotides; Saccharomyces cerevisiae, Schizosaccharomyces pombe; Fhit; tumor suppressor